Although the prior art shows locking systems for containers, none are believed to illustrate the type of device disclosed and claimed.
Storage containers referred to in the present specification are generally large, walk in boxes similar in size to semi-trailer trucks. The containers can be stacked and shipped by rail and by ship easily. In addition, such containers are used as storage devices by end users.
With any such container, maintaining security for the contents is a prime concern. Because such containers are often left unattended, they become targets for thieves and other criminals. Thus, the manufacturers and users of such containers continue to seek and develop better security techniques while the criminal element continues to develop methods for attacking and circumventing those security measures.
In addition, some storage applications require a seal around the doors to prevent entry of water, insects and other environmental elements. For example, paper and furniture storage is best served by a sealed container.
Various types of locking systems have been described in the prior art.
U.S. Pat. No. 5,029,909 entitled “Door Lock Assembly” which issued on Jul. 9, 1991 owned by assignee of the present invention discloses a protective device for locking the doors of a storage container using a two bar configuration.
U.S. Pat. No. 5,261,258 entitled “Padlock Protector” which issued on Nov. 16, 1993 owned by assignee of the present invention discloses a security device, which consists of an exterior mounted housing for a latch bar, which defines a recess. The recess provides access to an aperture in the bar by a circular shackle of a disk shaped padlock. This device operates in much the same fashion as the present invention. However, it is also believed to be less effective because of its exterior mounting and structure allows some access to the locking mechanism and the shaft by drills and hammer devices.
U.S. Pat. No. 5,509,700 entitled “Latch and Lock for Trailer Doors” which issued on Apr. 23, 1996 to Kennedy, Jr., and owned by assignee of the present invention, discloses a concealed latch with an arm attached to a pivot operatively connected to a pair of locking bars.
However, the devices of the prior art described above are not completely satisfactory. For example, such devices often require a great deal of effort to close and latch. In one system, the user is required to bend over and operate the lever system in a particular sequence. In addition, the devices are often difficult to operate if the container is not level. Further, these devices often provide only one locking mechanism making it possible, once the locking system has been circumvented, for thieves and other criminals to gain entry to the storage container.
Thus there is a need for a door locking system that is simple to operate, provides the necessary sealing action and provides a second locking mechanism that would require additional time to circumvent. The present invention meets this need.
None of the known prior art disclose the device set forth herein.